Table of Contents

1. Challenge

   Generate a Key Pair on the Client for SSH

   Note: For this lab, the use of a standalone terminal app with ssh support is best as the Instant Terminal does not permit port 61613. The instance does take a minute or so to be ready to be connected to via ssh. Please use port 61613 when connecting to this lab.

   ssh-keygen
   

2. Challenge

   Copy the Newly Created Key Over to the Server

   1. Open your newly created key (replace <PATH_TO_PUBLIC_KEY> with your path):

      vim <PATH_TO_PUBLIC_KEY>
      

   2. Select all and copy.

   3. Open /home/cloud_user/.ssh/authorized_keys:

      vim /home/cloud_user/.ssh/authorized_keys
      

   4. Paste in the public key.

   5. Save and quit:

      ESC
      :wq
      ENTER
      

3. Challenge

   Configure SSH to Not Allow Root Login or Password-Based Authentication and to Allow Key-Based Authentication

   1. Open the file:

      sudo vim /etc/ssh/sshd_config
      

   2. Make the following changes:

      PermitRootLogin no
      PasswordAuthentication no
      ChallengeResponseAuthentication no
      PubkeyAuthentication yes
      

   3. Save and quit:

      ESC
      :wq
      ENTER
      

   4. Restart the sshd service:

      sudo systemctl restart sshd
      

4. Challenge

   Test the New Configuration by Logging Out and Back in with the Newly Created Key

   1. Log out:

      exit
      

   2. Log in with the newly created key (replace <PATH_TO_PRIVATE_KEY> with your path):

      ssh cloud_user@SERVER_IP -p 61613 -i <PATH_TO_PRIVATE_KEY>